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Lorentz contraction 
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#73
Nov1609, 08:20 PM

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#74
Nov1609, 08:27 PM

P: 801

In a comoving reference frame, the ships get farther apart while the length of the string stays the same. The string breaks. In the launch frame, the ever increasing length contraction factor results in a constant distance between the ships, while the string gets "shorter". The string breaks. If the string stretches before it breaks, then the result of length contraction is that in the launch frame, the string's length is constant despite being stretched in its own frame. Length contraction doesn't mean contracting with time, it means contracted relative to the proper length. 


#75
Nov1609, 08:31 PM

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#76
Nov1609, 08:34 PM

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#77
Nov1609, 08:37 PM

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#78
Nov1609, 08:45 PM

P: 801

If the string stretches before it breaks, then the result of length contraction is that in the launch frame, the string's length is constant despite its proper length increasing with time. 


#79
Nov1609, 08:56 PM

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#80
Nov1609, 09:05 PM

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#81
Nov1609, 09:08 PM

P: 687

Where did you prove the string would snap from the POV of the launch frame? 


#82
Nov1609, 09:12 PM

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However, if we're just interested in the question of whether it snaps or not, we don't actually have to prove it from the perspective of multiple frames, proving it snaps using the perspective of any one frame is good enough, since in relativity all frames always agree on localized physical events. 


#83
Nov1609, 09:25 PM

P: 801

My only point was that the constant distance between the ships in the launch frame is "contracted" distance, and that "constant distance" and "increasingly lorentz contracted distance" aren't contradictory since the proper distance between the ships is increasing with time. 


#84
Nov1609, 09:29 PM

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#85
Nov1609, 09:33 PM

P: 687

Oh, this is where I am confused. Where is the string snap logic in the context of the launch frame? I mean, where is the math? It is certainly not in the SR acceleration equations or is it? 


#86
Nov1609, 09:34 PM

P: 687

This is legal. There is no distance differential in the launch frame for the ships. 


#87
Nov1609, 09:44 PM

P: 801

Are you asking for proof that a string's proper length can only increase so much before it breaks? 


#88
Nov1609, 09:58 PM

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#89
Nov1609, 10:01 PM

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#90
Nov1609, 10:12 PM

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